Largest DBs (any) you worked on?

ClickHouse cluster for web analytics data, 120 trillion records, mostly in two tables (hits and visits). 133 PiB uncompressed / 8.31 PiB compressed.

But it is not large compared to what other ClickHouse users have, for example:

> Ahrefs: main cluster is 100k+ CPU cores, 800TB RAM. 110PB nvme storage, uncompressed data size on main cluster is 1EB.

https://clickhouse.com/docs/en/about-us/adopters

Just a few hundred GBs of MySQL, which doesn't sound too big, but having tens of millions of rows can be tricky with some more complex query, to keep query time reasonable (within 1-2 seconds max).

~1.5 PB. Observability data.

size or disparate number of distinct dbs?

It was 25